This
element
identifies
another
resource
that
can
be
used
as
a
proxy
of
the
security
sensitivity
to
use
when
deciding
and
enforcing
access
control
rules
for
the
Binary
resource.
Given
that
the
Binary
resource
contains
very
few
elements
that
can
be
used
to
determine
the
sensitivity
of
the
data
and
relationships
to
individuals,
the
referenced
resource
stands
in
as
a
proxy
equivalent
for
this
purpose.
This
referenced
resource
may
be
related
to
the
Binary
(e.g.
Media,
DocumentReference),
or
may
be
some
non-related
Resource
purely
as
a
security
proxy.
E.g.
to
identify
that
the
binary
resource
relates
to
a
patient,
and
access
should
only
be
granted
to
applications
that
have
access
to
the
patient.

Very
often,
a
server
will
also
know
of
a
resource
that
references
the
binary,
and
can
automatically
apply
the
appropriate
access
rules
based
on
that
reference.
However,
there
are
some
circumstances
where
this
is
not
appropriate,
e.g.
the
binary
is
uploaded
directly
to
the
server
without
any
linking
resource,
the
binary
is
referred
to
from
multiple
different
resources,
and/or
the
binary
is
content
such
as
an
application
logo
that
has
less
protection
than
any
of
the
resources
that
reference
it.